Real World Differences between Mini35 and Alternatives

[Justine Haupt]

Hmmm... maybe we need a forum that reads "DOF adapters, both the P+S and all others".

I do truely understand things like the need for quality, reliability, support, etc. BUT, the one thing I care most about is quality (right, everyone?).

So, lets ignore everything else for a second and ask which has a better looking image. The P+S, or the best "other" brand out there?

I'm personally not convinced that the P+S actually looks any better.

I'm a DIYer, too, and a physics major... my adapter has erecting mirrors. My adapter has a CANON relay lens. It has adjustable flange focal distance and interchangeable lens mounts to which any lens can be attached. My adapter's image is SHARP. Very sharp... enough, that I still have to soften it in-camera, and there's no GG grain at all. It's made of solid aluminum on a rail support.

(I still having a vignetting and hotspotting isue, but I plan to have that completely resolved soon).

SO, my input is this... it all depends on one's abilities in optical engineering ;)

Admittedly, if I had the money I would consider the P+S, but even the new Letus v2 is a bit much for me right now, and it has a great image.

Even if the P+S were made from solid titanium and diamond, AND if it came with a new XL2, it would still be overpriced in my opinion. But if I could afford it, I just wouldn't care.

There probably won't be a truely subjective reply to this thread. Those that can not afford the P+S see how good the cheaper/DIY adapters can be. Those that can, can.

[Bob Hart]

Justin.

My guess is that with the P+S products the keywords might be trust and confidence and a product that is now more than one generation of development in a production environment .

The DIY projects are emulations of a concept which P+S put the R & D hard yards into though I qualify that comment with the rider that many of us builders may be arriving at similar solutions via sometimes convoluted, probably mostly parallel R&D paths of our own.

P+S techs, if they follow the DIY projects, might well sit back with a bit of a chuckle and the thought that some poor wretch is on a hiding to nowhere following a particular path.

Occasionally though, a dead end sometimes yields a result through a happens chance the original researchers did not experience.

In my own travels I have gained an understanding of the principles and can now operate my own machine with some confidence.

In relation to vignetting, hot spotting and sharpness of image, these items all interact. Regret to say, once you have solved you vignette and hot spot problem either with better optics or adjustments to groundglass texture, you will find resolution becomes second best. The trick is finding the balance.

The moment you break through that barrier, please don't keep it to yourself. The solution is there somewhere, just that P+S and the home brew population just haven't found it yet, or if they have, are keeping it to themselves for now.

In meantime, aim for 850 TV lines of resolution. I know it to be possible.

[Justine Haupt]

A small update in regards to my adapter! Bob, I think I have something (it's good enough for me, at least!). After a condenser lens upgrade, my vignetting is either gone or as of yet unnoticeable, I've not noticed a hotspot, and I still have the sharpness I had before.

The only side affect appears to be slight distortion, but in that assesment I'm not even confident. I don't believe the distortion is noticeable, or if it's even there. I feel like it's slightly "pin-cusioning" (which doesn't make sense given the bi-convex lens I'm using as a condenor), but verticle lines seem to remain verticle on the edges of the frame (as well as the center, of course). About the condenser... in experimenting, I was getting much better results with a BCX (as opposed to PCX), spaced about a centimeter from the GG, which seems to contradict everyone elses findings.

I plan to post some test footage in the alternative imaging forum in the next week.

I also plan to publish the plans and parts list online, eventually. I'm VERY happy with it right now (though I haven't done much testing with the new config).